Circuit-closer for trolley-signals.



' PATENTED AUG. 14, 1906.

H. THURSTON. CIRCUIT CLOSER FOR TROLLEY SIGNALS.

APPLICATION FILEDJAN. 2. 1906.

@Him/neg l HORACE THURSTON, OF PROVIDENCE, RHODE ISLAND.

CIRCUIT-CLOSER FOR TROLLEY-SIGNALAS.

Specification of Letters Patent.

Patented Aug. 14, 1906.

Application filed January 2. 1906. Serial NO- 294.10%

To all whom it may concern:

Beit known that I, HORACE THURs'roN, a citizen of the United States,residing at the city of Providence, in the county of Providence andState of Rhode Island, have invented certain new and useful Improvementsin Circuit Closers for Trolley Signals, of which the following is aspecification, reference being had therein to the accompanying drawings.

This invention relates to automatic signaling apparatus fortrolley-cars, and has for its object to provide a circuit-closer that ispreferably mounted on or near the trolley- Wire for'operating thesignals, said circuitcloser being actuated through a lever hanging inthe path of the passing trolley-wheel.

This invention is an improvement on my patent application forcircuit-closer for trollley-signals filed June 9, 1905, Serial No.264,449.

The contact made by the trolley-car upon the actuating-lever is veryshort even if the car is running at a moderate speed, and when the carproceeds at a high speed the contact on said lever is so short as to beentirely ineffective. Means therefore have been provided for prolongingthe electrical contact period to a suitable length of time to properlyoperate the signals that may be located at some distant point.

A further object of the invention is to so construct the device that asingle actuatinglever may be employed to operate a pair of contact-arms,so thatby moving said lever 'in one direction one of said contacts willbe closed and when moving in the opposite direction the other contactwill be closed.

The ordinary actuating-lever is made in one piece and depends into thepath of the trolley-wheel, and said lever is usually connected at itsupper end directly to the working mechanism. Therefore when therapidlypassing trolley-wheel strikes this lever the shock is transmittedimmediately through the same to the working mechanism and soon destroysthe parts. The trolley-wheel also when coming in contact with such alever is soonbattered up and destroyed, and the impact also has atendency to throw the wheel from the wire. All of these abovedifficulties are obviated in .my improved device which consists-,of ahinged or yielding tongue that is hung in the path of the trolley-wheel,so that when the trolley strikes the same it yields and swings to oneside without resistance, thereby materially reducing the initial l fshock both upon the wheel and the actuating mechanism. When the leverhas swung a predetermined distance, the wheel then rides easily underthe same, raising it comparatively slowly and readily removes thecontact-arms to close the circuit, thus materially relieving the initialshock and reducing the wear and tear on the mechanism.

This invention is also provided with a retarding device preferablycomprised of an oscillating air-compression cylinder, whereby aprolonged closure of the circuit is obtained whenever either of thecontact-arms is in connection, said cylinder being constructed to socontrol the movement of the contactarms that a quickmake and break ofthe contacts is obtained.

Another and most important feature of my resent invention is theconstruction by which the compression-cylinder is caused to positivelyprevent the making of a back contact. In practice, as is well known, itis necessary to make and break the connection quickly, and incontact-arm on leaving the contact-fingers often jumps over and makes aback contact on the opposite fingers. When this occurs, the signals areagain acted upon and completely disarranged, the whole system thenecoming unreliable, rendering traffic on a road equipped with such asystem dangerous. The above objections have been positively obviated bymy present construction, which is that of suspending thecompression-cylinder from the frame on two independent trunnions, saidtrunnions being attached to either side of the cylinder, whereby thecylinder in swinging to the center comes to a complete stop at once andwill not swing by, as is its tendency when hung on a single trunnion.

The invention is fully set forth in this sp ecification and moreparticularly pointed out in theappended claims.

In the accompanying drawings, Figure 1 is a side elevation of myimproved device, partly in section, showing the operating mechanism.Fig. 2 is an end view of the device, also partly in section.

Referring to the drawings, at 1 is the base doing this it is foundthatthe IOO of theframe that supports the mechanism, said base itselfbeing preferably supported from the trolley-wire in the usual way, (notshown,) or it may be supported by any other means adjacent said wire. Onthis base is mounted two supporting side frames 2 2, joined together attheir upper ends by the cap-plate 40, said plate being provided with aboss 41, depending from its center portion. Each frame 2 2 is providedwith two slots 42 43. These slots are each formed on the arc of acircle, the radius for each being taken from the center of the roundingportion at the bottom of the opposite slot. In these slots is suspendedthe cylinder 4 from its two trunnions 3 3. These trunnions may beconnected to the cylinder in any desired manner g but for convenienceThave cast bosses 3a 3a for them on either side of the cylinder-cap 5and fixed said trunnion-pins `3 3 therein to project out on either sideAthereof and engage their respective curved slots 42 43. This cap 5 ispreferably threaded to the upper end of lthe cylinder 4 and is providedwith an upwardly-extending boss 44, which boss corresponds to thedepending boss 41 from the cap-plate, and over both of these bosses isthe spring 45, exerting a tension against the cylinder-cap, therebyserving in addition to its gravity to cause said cylinderto set uprightland rest squarely on-both of its trunnions. This boss 44 is alsoprovided with an air-inlet passage 6, controlled by a ball-valve 7, saidvalve being kept normally closed by the action of the spring 8. Thisspring is inserted into the enlarged portion of the inlet and held inplace by the screw-plug 9. The lower end of this cylinder is alsoprovided with a threaded cap 10, which cap has an airvent 26 and aninwardly-projecting boss 117 which serves asa bearing for the piston-rod24. Mounted to slide in this cylinder is the piston l2, held normally inits up position by the action of the spring 13.

At 14 is an air-passage in the piston leading from its upper end downpart way through it and out through its side at 15 and in a position toregister with a hole 16 through the wall of the cylinder. This hole inthe piston is designed to register with the said hole in the cylinderwhen the pistonis on its upstroke and just as the contact-arms 17 17break their connection with the contact-fingers. `These two contact-arms17 17 are connected to a lever member 27 and set on an angle of aboutninety degrees' from each other, said lever member being pivoted belowat 18. Extending downwardly below this pivoting-point is the lever 19,and pivoted at 20 to the lower end of this lever is the dependingswinging forked tongue 21, straddling the trolley-wire 21a and hangingin thepath of the trolley-wheel. This tongue swings freely ineither-direction for-a short distance to j about the points marked A andC before it 6 5 brings up against the limit-lugs 22 and 23, after whicha further movement of said tongue in either direction actuates theoperating mechanism. A connecting-rod 24 is rigidly attached to thepiston 12 and extends down through the bearing 11 and is pivotallyconnected at 25 to the lever member 27. At 28 28 are two pair offlexible contact-fingers extending upward from their base-plates 29 and30. To these plates are connected the conductor-wires 31 and 32 by thebindingposts 33 and 34, and said plates are insulated at 35 and 36 fromthe frame 1. The whole of the mechanism may be covered over by anysuitable casing to protect the same from the weather, if desired.

The operation of the device maybe further described as follows: Thecylinder A4 is suspended on two independent trunnions 3 3, that arepreferably fixed on either side of the cylinder-head 5. When thecylinder is swung to the left, it is supported alone on its righttrunnion, the left one being raised in the slotted portion 42 in theframe 2, the reverse action taking place when the cylinder swings to theopposite side of the center. Owing to the use of the two trunnionsspread apart in the manner ind cated it is at once apparent that thecylinder has astrongv tendency to stop and hang suspended on bothtrunnions when it comes to the center and especially so when actingunder the pressure of the tensionspiring 45. Therefore bythisconstruction t e swinging byA or back contacting of the parts isentirely obviated. In addition to the above the piston 12, acting underthe influence ofthe spring 13, takes its uppermost position, which alsoserves to draw the contact-arms to their central position, both beingheld normally out of contactwith their contact-fingers on either-side,and when in this position the depending tongue 21 hangs over thetrolley-wire in position to engage the passing trolley-wheel. Supposingthe car to be approaching from the` right or in the direction indicatedby the arrow, when the trolley comes in contact with the dependingtongue the same yields and swings forward for a short distance into theposition shown by the dotted line at A without material y affecting amovement of the rest of the operating mechanism. As the .wheel continuesforward the tongue is forcedk from position A to position B, themovement of which carries the contact-arm 17 down on the opposite sidein between the flexible contact-fingers 28 to the position indicated thedotted line B, thereby swinging the pivoted cylinder 4 over to the rightand drawing the joint of the piston-rod down to the point B2. As thetrolley-wheel passes v out from under the tongue the spring 45, pressingdown on the cylinder-head- 5 actingl inA con- IOO IIO

IIS

back quickly junction with the spring 13 pressing upon the piston 12,would naturally throw the same and break the contact at once; but as thepiston is drawn down it automatically draws in air through theinlet-valve 7 and iills the` cylinder, which air is now trapped in thecylinder and allows the piston to return only as fast as said yair canleak out by the same. Therefore a slow return or a prolonged contact isassured; but when the contact-arm has reached the upper end oi thecontact-iingers the air-passage 14 in the piston registers with thevent-hole 16 in the cylinder, allowing the pressure of air to escapetherethrough, and the piston thus relieved springs upward and with aquick jump draws the contact-arm Jfrom between the contactfingers, thuspreventing the objectionable arc. The quick make and break of theconnections in devices of this character where high-tension currents areused are, as is well known, vital to its practical working. Theretarding of the return action of the piston allows the contact-arin toremain in connection a suicient length of time to insurea completion ofthe circuit, and consequentlya sure operation of the signals. To work inconjunction with the double trunnions to prevent a connection being madewith the opposite contact-iingers by the force of the quick jump of thecontact-arms, I have arranged the air-passage 15 in the piston, so thatit will have passed and closed the kvent 16 in the cylinder just beforethe piston reaches the upper end of its stroke, thereby trapping the airin the top of the cylinder to form a cushion and again retarding thelast end of the upward stroke of the piston, thereby causin themechanism to come slowly to its centra or stop position. Thedoubletrunnions construction working in conjunction with thispiston-trap arrangement obviates any possibility of the contact-armsgoing past and nia ring a connection on the opposite side.

rIhe device is extremely simple and practical iii construction and mosteiective in its operation. Y

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. In a circuit-closer, a pair of contacts, a pair of contact-arms,means whereby said arms may be actuated to close the circuit by apassing car, means including a piston working in a cylinder forautomatically prolonging the period of contact, means in said cylinderfor causing a quick break in the connection, and means for preventing aback contact.

2, In a circuit-closer, a pair of contacts, a pair of contact-arms,means whereby said arms may be actuated to close the circuit each time acar passes, means including a movable cylinder for prolonging the periodof contact and causing a quick break in the connection.

3. In a circuit-closer, a pair of contacts, a

pair of contact-arms, means whereby said arms may be actuated to closethe circuit each time a car passes, means including an oscillatingcylinder Jfor automatically prolonging the period of contact, means insaid cylinder for causing a quick break in the connection, and means forcausing the swinging cylinder to stop on coming to its central position.

4. In a circuit-closer, a pair of contacts, a pairy of contact-arms,means whereby said arms are actuated to close the circuit by a passingcar, a piston in a swinging cylinder for automatically prolonging theContact, means for causing a quick break in the connection, and means insaid cylindersupport whereby said cylinder is stopped from swinging toprevent the contact-arm from making a back contact.

5. In a circuit-closer, a pair pair of contact-arms, means whereby saidarms are actuated to close the circuit by a passing car, a piston in aswinging cylinder for automatically prolonging the period of contact,means for causing a quick break in the connection, and means including apair of trunnions on which said cylinder is supperiod of l of contacts,a

ported, whereby the cylinder is stopped from I swinging at apredetermined point to prevent the contact-arm from making. a backcontact. v

6. In a circuit-closer, a pair of contacts, a pair of contact-arms,means whereby said arms may be actuated to close the circuit each time acar passes, means including a piston working in an oscillating cylinderfor automatically prolonging the contact period, means in said cylinderJfor causing a quick break in the connection, `and means including apair of trunnions on which said cylinder is suspended Jfor causing theswinging cylinder to stop on coming to the central position.

7. In a circuit-closer, a pair of contacts, a pair of contact-arms,means including a yieldable depending tongue through which said 'armsare actuated to close the circuit by a passing car, means forautomatically pro- IOO IIO

longing the period of contact, and means for ing in a cylinder forautomatically prolonging the period of contact and causing a quick breakin the connection, and means connected to said cylinder for preventing aback contact.

l 9. In a circuit-closer, a pair of contacts, a

IZO

pair of contact-arms7 means whereby said ing at a predetermined point toprevent the arms are actuated to close the circuit by a contact-arm frommaking a back contact. 1o passing car, a piston in a swinging cylinderIn testimony whereof I aliX my signature for automatically prolongingthe period of in presence of tWo Witnesses.

ContactJ means for causing a quick break in HORACE THURSTON. theconnection, and means including a pair of Witnesses:

trunnions on Which said cylinder is supported HOWARD E. BARLOW. wherebythe cylinder is stopped from sWingl E. D. OGDEN.

